include/linux/cpuset.h

   1 #ifndef _LINUX_CPUSET_H
   2 #define _LINUX_CPUSET_H
   3 /*
   4  *  cpuset interface
   5  *
   6  *  Copyright (C) 2003 BULL SA
   7  *  Copyright (C) 2004-2006 Silicon Graphics, Inc.
   8  *
   9  */
  10
  11 #include <linux/sched.h>
  12 #include <linux/cpumask.h>
  13 #include <linux/nodemask.h>
  14 #include <linux/mm.h>
  15
  16 #ifdef CONFIG_CPUSETS
  17
  18 extern int number_of_cpusets;   /* How many cpusets are defined in system? */
  19
  20 extern int cpuset_init(void);
  21 extern void cpuset_init_smp(void);
  22 extern void cpuset_update_active_cpus(bool cpu_online);
  23 extern void cpuset_cpus_allowed(struct task_struct *p, struct cpumask *mask);
  24 extern void cpuset_cpus_allowed_fallback(struct task_struct *p);
  25 extern nodemask_t cpuset_mems_allowed(struct task_struct *p);
  26 #define cpuset_current_mems_allowed (current->mems_allowed)
  27 void cpuset_init_current_mems_allowed(void);
  28 int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask);
  29
  30 extern int __cpuset_node_allowed_softwall(int node, gfp_t gfp_mask);
  31 extern int __cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask);
  32
  33 static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
  34 {
  35         return number_of_cpusets <= 1 ||
  36                 __cpuset_node_allowed_softwall(node, gfp_mask);
  37 }
  38
  39 static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
  40 {
  41         return number_of_cpusets <= 1 ||
  42                 __cpuset_node_allowed_hardwall(node, gfp_mask);
  43 }
  44
  45 static inline int cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
  46 {
  47         return cpuset_node_allowed_softwall(zone_to_nid(z), gfp_mask);
  48 }
  49
  50 static inline int cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
  51 {
  52         return cpuset_node_allowed_hardwall(zone_to_nid(z), gfp_mask);
  53 }
  54
  55 extern int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
  56                                           const struct task_struct *tsk2);
  57
  58 #define cpuset_memory_pressure_bump()                           \
  59         do {                                                    \
  60                 if (cpuset_memory_pressure_enabled)             \
  61                         __cpuset_memory_pressure_bump();        \
  62         } while (0)
  63 extern int cpuset_memory_pressure_enabled;
  64 extern void __cpuset_memory_pressure_bump(void);
  65
  66 extern void cpuset_task_status_allowed(struct seq_file *m,
  67                                         struct task_struct *task);
  68 extern int proc_cpuset_show(struct seq_file *, void *);
  69
  70 extern int cpuset_mem_spread_node(void);
  71 extern int cpuset_slab_spread_node(void);
  72
  73 static inline int cpuset_do_page_mem_spread(void)
  74 {
  75         return current->flags & PF_SPREAD_PAGE;
  76 }
  77
  78 static inline int cpuset_do_slab_mem_spread(void)
  79 {
  80         return current->flags & PF_SPREAD_SLAB;
  81 }
  82
  83 extern int current_cpuset_is_being_rebound(void);
  84
  85 extern void rebuild_sched_domains(void);
  86
  87 extern void cpuset_print_task_mems_allowed(struct task_struct *p);
  88
  89 /*
  90  * get_mems_allowed is required when making decisions involving mems_allowed
  91  * such as during page allocation. mems_allowed can be updated in parallel
  92  * and depending on the new value an operation can fail potentially causing
  93  * process failure. A retry loop with get_mems_allowed and put_mems_allowed
  94  * prevents these artificial failures.
  95  */
  96 static inline unsigned int get_mems_allowed(void)
  97 {
  98         return read_seqcount_begin(&current->mems_allowed_seq);
  99 }
 100
 101 /*
 102  * If this returns false, the operation that took place after get_mems_allowed
 103  * may have failed. It is up to the caller to retry the operation if
 104  * appropriate.
 105  */
 106 static inline bool put_mems_allowed(unsigned int seq)
 107 {
 108         return !read_seqcount_retry(&current->mems_allowed_seq, seq);
 109 }
 110
 111 static inline void set_mems_allowed(nodemask_t nodemask)
 112 {
 113         unsigned long flags;
 114
 115         task_lock(current);
 116         local_irq_save(flags);
 117         write_seqcount_begin(&current->mems_allowed_seq);
 118         current->mems_allowed = nodemask;
 119         write_seqcount_end(&current->mems_allowed_seq);
 120         local_irq_restore(flags);
 121         task_unlock(current);
 122 }
 123
 124 #else /* !CONFIG_CPUSETS */
 125
 126 static inline int cpuset_init(void) { return 0; }
 127 static inline void cpuset_init_smp(void) {}
 128
 129 static inline void cpuset_update_active_cpus(bool cpu_online)
 130 {
 131         partition_sched_domains(1, NULL, NULL);
 132 }
 133
 134 static inline void cpuset_cpus_allowed(struct task_struct *p,
 135                                        struct cpumask *mask)
 136 {
 137         cpumask_copy(mask, cpu_possible_mask);
 138 }
 139
 140 static inline void cpuset_cpus_allowed_fallback(struct task_struct *p)
 141 {
 142 }
 143
 144 static inline nodemask_t cpuset_mems_allowed(struct task_struct *p)
 145 {
 146         return node_possible_map;
 147 }
 148
 149 #define cpuset_current_mems_allowed (node_states[N_MEMORY])
 150 static inline void cpuset_init_current_mems_allowed(void) {}
 151
 152 static inline int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)
 153 {
 154         return 1;
 155 }
 156
 157 static inline int cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
 158 {
 159         return 1;
 160 }
 161
 162 static inline int cpuset_node_allowed_hardwall(int node, gfp_t gfp_mask)
 163 {
 164         return 1;
 165 }
 166
 167 static inline int cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
 168 {
 169         return 1;
 170 }
 171
 172 static inline int cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
 173 {
 174         return 1;
 175 }
 176
 177 static inline int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
 178                                                  const struct task_struct *tsk2)
 179 {
 180         return 1;
 181 }
 182
 183 static inline void cpuset_memory_pressure_bump(void) {}
 184
 185 static inline void cpuset_task_status_allowed(struct seq_file *m,
 186                                                 struct task_struct *task)
 187 {
 188 }
 189
 190 static inline int cpuset_mem_spread_node(void)
 191 {
 192         return 0;
 193 }
 194
 195 static inline int cpuset_slab_spread_node(void)
 196 {
 197         return 0;
 198 }
 199
 200 static inline int cpuset_do_page_mem_spread(void)
 201 {
 202         return 0;
 203 }
 204
 205 static inline int cpuset_do_slab_mem_spread(void)
 206 {
 207         return 0;
 208 }
 209
 210 static inline int current_cpuset_is_being_rebound(void)
 211 {
 212         return 0;
 213 }
 214
 215 static inline void rebuild_sched_domains(void)
 216 {
 217         partition_sched_domains(1, NULL, NULL);
 218 }
 219
 220 static inline void cpuset_print_task_mems_allowed(struct task_struct *p)
 221 {
 222 }
 223
 224 static inline void set_mems_allowed(nodemask_t nodemask)
 225 {
 226 }
 227
 228 static inline unsigned int get_mems_allowed(void)
 229 {
 230         return 0;
 231 }
 232
 233 static inline bool put_mems_allowed(unsigned int seq)
 234 {
 235         return true;
 236 }
 237
 238 #endif /* !CONFIG_CPUSETS */
 239
 240 #endif /* _LINUX_CPUSET_H */